Mumbai Enforces GRAP-4 Curbs as AQI Spikes Above 300; 53 Construction Sites Issued Stop-Work Notices

The Brihanmumbai Municipal Corporation (BMC) has activated GRAP-4 restrictions in several pockets of Mumbai after the city recorded Air Quality Index (AQI) levels between 200 and 300 for consecutive days because of the rising PM2.5 and PM10 concentrations. The poor air quality, mainly because of the construction dust, vehicular emissions, and industrial activity, forced the civic body to take targeted action to curb pollution sources.

Unlike Delhi, where GRAP-4 triggers citywide shutdowns and school closures, Mumbai's approach is only preventive, with a focus on stopping high-dust activities in hotspot zones.

Why GRAP-4 Was Triggered in Mumbai

BMC initiated GRAP-4 measures after several areas crossed the "very poor" AQI threshold of 301 to 400, with some pockets briefly entering the "severe" category above 400. The enforcement began after the AQI remained above 200 for three straight days, post which a directive from BMC Commissioner Bhushan Gagrani was issued.

The corporation deployed 95 flying squads across Mumbai's 26 wards, inspecting more than 70 construction and RMC sites. By late November, 53 units had been served stop-work notices for non-compliance with dust-control norms.

Affected Areas and AQI Levels

Several neighbourhoods reported intense pollution, with residents complaining of breathing difficulty, eye irritation, and reduced visibility. Areas that experienced high AQI spikes include:

Mazgaon, where the AQI climbed to 259, Deonar, Malad West, Borivali East, Chakala-Andheri East, Navy Nagar, Powai, and Mulund.

Although Mumbai's overall AQI stood at 111 ("moderate") on December 1, earlier peaks in key hotspots reached 342-457, significantly above safe levels. Post-enforcement, AQI dropped in some pockets to around 158, indicating early signs of improvement.

Latest AQI Readings from IQAir (December 1)

According to IQAir, real-time AQI readings across Mumbai On December 1, 2025, most areas showed significant improvement amid ongoing GRAP-4 enforcement, with Bandra-Hill Road topping the list at 179 (unhealthy for sensitive groups), followed by Borivali at 158, Byculla (BMC) at 156, Chembur (MPCB) at 150, Mumbai Airport T2 (MPCB) at 122, Bandra Kurla Complex (MPCB) at 112, Ghatkopar (BMC) at 111, Borivali East (MPCB) at 104, Colaba (MPCB) at 94, and Deonar (IITM) at 84 (moderate).

GRAP-4 Restrictions Implemented by BMC

Construction Curbs

This includes a complete ban on dust-generating activities at violating sites. Mandatory water sprinkling, wind barriers, and barricading. Additionally, stop-work notices were issued to non-compliant construction and RMC plants.

Industrial Controls

Small industrial units like bakeries and marble-cutting workshops have been ordered to switch to cleaner fuels. Closure warnings issued for non-compliance. The authorities have assigned 450 junior supervisors to fine violators for debris dumping and garbage burning.

Road & Traffic Measures

To curb the pollution caused by traffic, mechanised sweeping and water sprinkling have been intensified on major roads. Stricter PUC (Pollution Under Control) checks for vehicles are organised. Restrictions on truck entry in high-pollution zones

The measures will remain in effect until AQI levels improve sustainably across the affected zones.